Serum microRNA profiles in athyroid patients on and off levothyroxine therapy

Background Levothyroxine replacement treatment in hypothyroidism is unable to restore physiological thyroxine and triiodothyronine concentrations in serum and tissues completely. Normal serum thyroid stimulating hormone (TSH) concentrations reflect only pituitary euthyroidism and, therefore, novel biomarkers representing tissue-specific thyroid state are needed. MicroRNAs (miRNAs), small non-coding regulatory RNAs, exhibit tissue-specific expression patterns and can be detectable in serum. Previous studies have demonstrated differential expression of (precursors of) miRNAs in tissues under the influence of thyroid hormone. Objective To study if serum miRNA profiles are changed in different thyroid states. Design and methods We studied 13 athyroid patients (6 males) during TSH suppressive therapy and after 4 weeks of thyroid hormone withdrawal. A magnetic bead capture system was used to isolate 384 defined miRNAs from serum. Subsequently, the TaqMan Array Card 3.0 platform was used for profiling after individual target amplification. Results Mean age of the subjects was 44.0 years (range 20–61 years). Median TSH levels were 88.9 mU/l during levothyroxine withdrawal and 0.006 mU/l during LT4 treatment with a median dosage of 2.1 μg/kg. After normalization to allow inter-sample analysis, a paired analysis did not demonstrate a significant difference in expression of any of the 384 miRNAs analyzed on and off LT4 treatment

Report on short-term side effects of treatments with 177Lu- octreotate in combination with capecitabine in seven patients with gastroenteropancreatic neuroendocrine tumours

Purpose: Treatment with the radiolabelled somatostatin analogue177Lu-octreotate results in tumour remission in 47% of patients with gastroenteropancreatic neuroendocrine tumours. Adding capecitabine to177Lu-octreotate, as a radio-sensitiser, may enhance these anti-tumour effects. We now present the short-term toxicity profile of this novel combination. Methods: Seven patients were treated with 7.4 GBq177Lu-octreotate and capecitabine (1650 mg/m2per day) for 2 weeks with an intended number of four cycles. Toxicity, and especially haematological and renal parameters, were monitored on a weekly basis for the first two cycles and 4 and 6 weeks after subsequent cycles. Results: None of the patients had hand-foot syndrome. One patient had grade 1 stomatitis occurring after one of four cycles. Grade 3 or 4 leukopenia or neutropenia did not occur. One patient had grade 3 anaemia, but none had grade 4 anaemia. One patient had grade 2 thrombocytopenia after the fourth cycle, and one had grade 3 thrombocytopenia. Grade 4 thrombocytopenia did not occur. No significant changes in serum creatinine levels were observed. None of the patients had symptoms of cardiac ischaemia. Conclusions: Treatment with the combination of177Lu-octreotate and capecitabine was feasible and safe considering acute and subacute side effects. We therefore started a randomised, controlled clinical trial to compare this combination with177Lu-octreotate as single agent with regard to anti-tumour effects and side effects

Serum microRNA profiles in athyroid patients on and off levothyroxine therapy

BackgroundLevothyroxine replacement treatment in hypothyroidism is unable to restore physiological thyroxine and triiodothyronine concentrations in serum and tissues completely. Normal serum thyroid stimulating hormone (TSH) concentrations reflect only pituitary euthyroidism and, therefore, novel biomarkers representing tissue-specific thyroid state are needed. MicroRNAs (miRNAs), small non-coding regulatory RNAs, exhibit tissue-specific expression patterns and can be detectable in serum. Previous studies have demonstrated differential expression of (precursors of) miRNAs in tissues under the influence of thyroid hormone.ObjectiveTo study if serum miRNA profiles are changed in different thyroid states.Design and methodsWe studied 13 athyroid patients (6 males) during TSH suppressive therapy and after 4 weeks of thyroid hormone withdrawal. A magnetic bead capture system was used to isolate 384 defined miRNAs from serum. Subsequently, the TaqMan Array Card 3.0 platform was used for profiling after individual target amplification.ResultsMean age of the subjects was 44.0 years (range 20-61 years). Median TSH levels were 88.9 mU/I during levothyroxine withdrawal and 0.006 mU/I during LT4 treatment with a median dosage of 2.1 fag/kg. After normalization to allow inter-sample analysis, a paired analysis did not demonstrate a significant difference in expression of any of the 384 miRNAs analyzed on and off LT4 treatment.ConclusionAlthough we previously showed an up-regulation of pri-miRNAs 133b and 206 in hypothyroid state in skeletal muscle, the present study does not supply evidence that thyroid state also affects serum miRNAs in humans

Hormonal crises following receptor radionuclide therapy with the radiolabeled somatostatin analogue [177Lu-DOTA0,Tyr3]octreotate

textabstractIntroduction: Receptor radionuclide therapy is a promising treatment modality for patients with neuroendocrine tumors for whom alternative treatments are limited. The aim of this study was to investigate the incidence of hormonal crises after therapy with the radiolabeled somatostatin analogue [177Lu-DOTA0,Tyr3]octreotate (177Lu-octreotate). Materials and methods: All177Lu- octreotate treatments between January 2000 and January 2007 were investigated. Four hundred seventy-six patients with gastroenteropancreatic neuroendocrine tumors and three patients with metastatic pheochromocytoma were included for analysis. Results: Four hundred seventy-nine patients received a total of 1,693 administrations of177Lu-octreotate. Six of 479 patients (1%) developed severe symptoms because of massive release of bioactive substances after the first cycle of177Lu-octreotate. One patient had a metastatic hormone-producing small intestinal carcinoid; two patients had metastatic, hormone-producing bronchial carcinoids; two patients had vasoactive intestinal polypeptide-producing pancreatic endocrine tumors (VIPomas); and one patient had a metastatic pheochromocytoma. With adequate treatment, all patients eventually recovered. Conclusion: Hormonal crises after177Lu- octreotate therapy occur in 1% of patients. Generally,177Lu- octreotate therapy is well tolerated

Recurrent differentiated thyroid cancer: Towards personalized treatment based on evaluation of tumor characteristics with PET (THYROPET Study): Study protocol of a multicenter observational cohort study

Background: After initial treatment of differentiated thyroid carcinoma (DTC) patients are followed with thyroglobulin (Tg) measurements to detect recurrences. In case of elevated levels of Tg and negative neck ultrasonography, patients are treated 'blindly' with Iodine-131 (131I). However, in up to 50% of patients, the post-therapy scan reveals no 131I-targeting of tumor lesions. Such patients derive no benefit from the blind therapy but are exposed to its toxicity. Alternatively, iodine-124 (124I) Positron Emission Tomography/Computed Tomography (PET/CT) has become available to visualize DTC lesions and without toxicity. In addition to this, 18F-fluorodeoxyglucose (18F-FDG) PET/CT detects the recurrent DTC phenotype, which lost the capacity to accumulate iodine. Taken together, the combination of 124I and 18F-FDG PET/CT has potential to stratify patients for treatment with 131I.Methods/Design: In a multicenter prospective observational cohort study the hypothesis that the combination of 124I and 18F-FDG PET/CT can avoid futile 131I treatments in patients planned for 'blind' therapy with 131I, is tested.One hundred patients planned for 131I undergo both 124I and 18F-FDG PET/CT after rhTSH stimulation. Independent of the outcome of the scans, all patients will subsequently receive, after thyroid hormone withdrawal, the 131I therapy. The post 131I therapeutic scintigraphy is compared with the outcome of the 124I and 18F-FDG PET/CT in order to evaluate the diagnostic value of the combined PET modalities.This study primary aims to reduce the number of futile 131I therapies. Secondary aims are the nationwide introduction of 124I PET/CT by a quality assurance and quality control (QA/QC) program, to correlate imaging outcome with histopathological features, to compare 124I PET/CT after rhTSH and after withdrawal of thyroid hormone, and to compare 124I and 131I dosimetry.Discussion: This study aims to evaluate the potential value of the combination of 124I and 18F-FDG PET/CT in the prevention of futile 131I therapies in patients with biochemically suspected recurrence of DTC. To our best knowledge no studies addressed this in a prospective cohort of patients. This is of great clinical importance as a futile 131I is a costly treatment associated with morbidity and therefore should be restricted to those likely to benefit from this treatment.Trial registration: Clinicaltrials.gov identifier: NCT01641679

Upfront treatment of high-risk neuroblastoma with a combination of 131I-MIBG and topotecan

(131)I-metaiodobenzylguanidine ((131) I-MIBG) has a significant anti-tumor effect against neuroblastoma (NBL). Topotecan (TPT) can act as a radio-sensitizer and can up-regulate (131) I-MIBG uptake in vitro in NBL. Determine the efficacy of the combination of (131) I-MIBG with topotecan in newly diagnosed high-risk (HR) NBL patients. In a prospective, window phase II study, patients with newly diagnosed high-risk neuroblastoma were treated at diagnosis with two courses of (131) I-MIBG directly followed by topotecan (0.7 mg/m(2) for 5 days). After these two courses, standard induction treatment (four courses of VECI), surgery and myeloablative therapy (MAT) with autologous stem cell transplantation (ASCT) was given. Response was measured after two courses of (131) I-MIBG-topotecan and post MAT and ASCT. Hematologic toxicity and harvesting of stem cells were analysed. Topoisomerase-1 activity levels were analysed in primary tumor material. Sixteen patients were included in the study; median age was 2.8 years. MIBG administered activity (AA) (median and range) of the first course was 0.5 (0.4-0.6) GBq/kg (giga Becquerel/kilogram) and of the second course 0.4 (0.3-0.5) GBq/kg. The overall objective response rate (ORR) after 2 × MIBG/TPT was 57%, the primary tumor RR was 94%, and bone marrow RR was 43%. The ORR post MAT and ASCT was 57%. Hematologic grade four toxicity: after first and second (131) I-MIBG (platelets 25/33%, neutrophils 13/33%, and hemoglobin 25/7%). Topoisomerase-1 activity levels were increased in 10/10 (100%) measured tumors. Combination therapy with MIBG-topotecan is an effective window treatment in newly diagnosed high-risk neuroblastoma patient

Predictive value of CYP3A and ABCB1 phenotyping probes for the pharmacokinetics of sunitinib : the ClearSun study

Background and Objective: The wide inter-patient variability in drug exposure partly explains the toxicity and efficacy profile of sunitinib treatment. In this prospective study cytochrome P450 (CYP) 3A and adenosine triphosphate binding cassette (ABC) B1 phenotypes were correlated to the pharmacokinetics of sunitinib and its active metabolite N-desethylsunitinib. Methods: A correlation analysis was performed between sunitinib pharmacokinetics and 1?OH-midazolam/midazolam ratio and parameters derived from technetium-99m-2-methoxy isobutyl isonitrile (99mTc-MIBI) scans, respectively. A population pharmacokinetic model using non-linear mixed-effects modeling software NONMEM was built, which included the phenotype tests as covariate. Results: In 52 patients, the mean trough concentration of sunitinib plus metabolite increased from 21.4 ng/mL at day 1 of a cycle to 88.1 ng/mL in the fourth week of treatment. A trend for a correlation was observed between 99mTc-MIBI elimination constant and trough concentrations of N-desethylsunitinib; however, this was not significant. Correlations were found between 1?OH-midazolam/midazolam ratio and sunitinib clearance (P = 0.008) and day 1 N-desethylsunitinib trough concentrations (P = 0.005), respectively. Moreover, patients suffering from grade 3 toxicities had significant lower clearance of sunitinib than patients without grade 3 toxicities (34.4 vs. 41.4 L/h; P = 0.025). Conclusions: Phenotype tests for ABCB1 and CYP3A4 did not explain inter-individual variability of sunitinib exposure sufficiently. However, the correlation between sunitinib clearance and the occurrence of severe toxicity suggests a direct exposure-toxicity relationship.9 page(s